What’s Up in the Night Sky? June 2020 by Fred Barrett

Jun 10, 2020

The Moon is leaving us! Well, not right away. I’ve mentioned in a few columns over the past few years that the only reason that we have a solar eclipse is that the Moon is at the exact right distance to block the Sun completely. In the very distant past, it was much closer – frighteningly close. It has been slowly moving farther away. Why? Its orbital velocity has been slowly increasing and the faster you go when you orbit a body, the farther out you move from that body. How can the Moon’s velocity be increasing? It‘s essentially a dead world and doesn’t have any internal heat to vent plumes of gas to boost its motion like a rocket ship. Right now the Moon is receding by about 3.8 cm (1.5 in) per year. It’s hardly a runaway escape attempt but, still, a movement that can’t be ignored. The explanation has to do with gravity. How? Gravity usually attracts, doesn’t it? It depends on what is being attracted. The Earth and Moon exert a gravitational force to keep them orbiting each other. This force also causes the tides that we see all over our planet every day. Because of the Earth’s rotation rate, the time that high tides occur is just ahead of the Moon and not directly underneath it. The Moon is attracted by the greater mass just ahead of it and its orbital speed is slightly increased and it orbits slightly farther out. The distance increase is dreadfully slow and I really mean slow. But wait! The Moon has a gravity effect on Earth. The tides that it causes create friction which slowly decreases the rotation rate of the Earth. As I said above, the Moon used to be much closer to our planet. Earth was rotating much faster too. As the Moon gets farther away, it will continue to slow our rotation. Eventually, in about 50 billion years, the amount of time it takes for the Moon to orbit Earth once, will match the time it takes for the Earth to rotate once – 47 of our current Earth days. The orbits will be finally stabilized. The Moon should be pretty tiny by then in that unlikely future since the Sun is only good for another 5 billion years. By that time we will have been vaporized by the red giant phase of our Sun as it heads to extinction in its final, dim white dwarf ending. Hopefully, the human race will have expanded to a Galactic existence and be off exploring greener pastures.

Karen Prytula, one of our Frontenac News community reporters for Maberly-Bolingbroke, dropped off a special treat for me in my post box. It was a September 13, 1944 issue of Family Herald and Weekly Star, Canada’s National Farm Magazine. Karen is very much a local historical buff and it was a fascinating newspaper, especially the advertising. She had an ulterior motive for the drop off. On page 47, as she had written on the front, I was to look for an astronomy column called Study of the Skies. It was by Jane Davis, Staff Editor Amateur Astronomer Association, New York City. Although a trifle dry, it reported where to find all the astronomical highlights of the month and included a small sky map for September/ 1944. It pretty much matches my sky map (looking south) for September 15, 2020, 8 pm. Rest assured that the sky is all still where it should be except for all those pesky satellites whizzing overhead. Thank you Karen.

There’s a special treat again this month having to do with Jupiter and Saturn. Look to the south southwest about 2 hours before dawn around mid month and you will see the solar system’s 2 largest planets within 5 degrees of each other. Binoculars will enhance your view and Saturn’s rings will be spectacular in a small scope.

Venus becomes a morning star in the east this month in the predawn sky. Mars will be in opposition 4 months from now and I mention that because having Mars at its closest approach provides golden opportunities for observing. You will find it in the south east at mid month. It will be moving quickly through Aquarius.

Here are some highlights for June.

June 8: Moon passes is 3 degrees south of Saturn at 10 pm.

June 12: The Moon is 3 degrees south of Mars at 8 pm.

June 13: Last quarter Moon.

June 14: The Moon is at apogee (farthest) 402,250 Kms.

June 19: The Moon passes less than 1 degree north of Venus at 5 am.

June 20: Summer Solstice is at 5:44 pm. Spring has barely arrived and now we’re sliding towards winter.

June 21: New Moon.

June 28: First quarter Moon.

June 29: The Moon is at perigee (closest) 366,820 Kms.

That’s a wrap. Clear skies and keep looking up!

“The Beginner’s Observing Guide by Leo Enright is an invaluable companion for adventures in the sky. It also contains useful star charts. It can be ordered from the Royal Astronomical Society of Canada at www.rasc.ca/publications. A subscription to our very own excellent Canadian astronomy magazine “SkyNews” can be arranged at the RASC website as well.

Let me know how your observing has gone this month, especially anything unusual. I enjoy the feedback. If you have any questions or suggestions you can contact me through this paper or email me at This email address is being protected from spambots. You need JavaScript enabled to view it. . Clear Skies! Fred.